P2504

P2504-CHARGING SYSTEM OUTPUT HIGH





For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
The engine running. The engine speed greater than 1157 RPM.

- Set Condition:
The PCM compares the B+ feed to the Generator with the Gen Sense circuit. If the Gen Sense voltage input to the PCM is greater than the B+ voltage the DTC will set. One Trip Fault. Three good trips to turn off the MIL.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Initial Inspection and Diagnostic Overview.

Diagnostic Test

1. ACTIVE DTC

NOTE: Inspect the vehicle for aftermarket accessories that may exceed the Generator System output.

Ignition on, engine not running.

NOTE: The battery must be fully charged.

NOTE: The Generator belt tension and condition must be checked before continuing.

With a scan tool, read DTCs.
With a scan tool, erase DTCs.
Start the engine.
Allow the idle to stabilize.
With the scan tool, read DTCs.
Is the DTC active at this time?

Yes

- Go To 2

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure.Intermittent Condition
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

2. FUSED B+ CIRCUIT HIGH RESISTANCE
NOTE: Inspect the Generator harness connector and the Generator Eyelet for corrosion or damage before continuing.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

Ignition on, engine not running.

NOTE: Make sure all wires are clear of the engine's moving parts.

Measure the voltage between the Generator B+ Output Terminal and the Battery+ Post.
Start the engine.
Is the voltage above 0.4 of a volt?

Yes

- Repair the excessive resistance in the battery positive circuit between the Generator and Battery.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 3

3. EXCESSIVE RESISTANCE IN THE CASE GROUND

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

Start the engine.
Warm the engine to operating temperature.

NOTE: Make sure all wires are clear of the engine's moving parts.

Measure the voltage between the Generator Case and Battery ground post.
Is the voltage above 0.1 of a volt?

Yes

- Repair the excessive resistance in the Generator Case Ground.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 4

4. (A803/A804) GEN SENSE CIRCUIT SHORTED TO BATTERY VOLTAGE




Turn the ignition off.
Disconnect the Generator harness connector.
Disconnect the PCM harness connectors.
Turn the ignition on.
Measure the voltage on the (A803/A804) Gen Sense circuit in the Generator Field harness connector.
Does the voltameter indicate voltage present?

Yes

- Repair the short to battery voltage in the (A803/A804) Gen Sense circuit.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Go To 5

5. INTERNAL HIGH RESISTANCE GENERATOR

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts, or fan. Do not wear loose clothing. Failure to follow these instructions can result in personal injury or death.

Turn the ignition off.
Reconnect the Generator harness connector.
Reconnect the PCM Harness connector.

NOTE: Make sure all wires are clear of the engine's moving parts.

Measure the voltage between the Generator Eyelet terminal and the Gen Sense circuit in the Generator harness connector.
Start the engine.
Is the voltage above 0.1 of a volt?

Yes

- Replace the Generator.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Replace the Powertrain Control Module.
- Perform the POWERTRAIN VERIFICATION TEST. Powertrain Verification Test